Chain-stitch sewing-machine.



C. P. HOLMES.

CHAIN STITCH SEWING MACHINE.

APPLICATION FILED mmwz. 1012 1,116,353, Patented Nov. 3, 1914.

5 SHEETS" SHEET 1.

G. P. HOLMES.

CHAIN STITCH SEWING MACHINE.

6 SHEETS-SHEBT 2.

APPLIUATION TILED MAB. 22,1912. 1,1 16,353, Patented Nov. 3, 1914.

I I I I G. P. HOLMES.

CHAIN STITCH SEWING MACHINE.

5 SHEETS-SHEET 3.

Patented Nov. 3, 1914.

APPLICATION FILED MAR 22, 1912.

C. P. HOLMES.

CHAIN STITCH SEWING MACHINE.

APrLIGATION TILED MAR. 22, 1912 1,116,353. Patented Nov. 3, 1914.

5 SHEETS-SHEET l,

G. P. HOLMES.

CHAIN STITCH SEWING MACHINE.

APPLICATION IILBD MAB.22,1912.

Patented Nov. 3, 1914.

1 6,353 5 sums-sum 5 aw. F 6A V 'IIIIIIIIIIIIZ LAM *YW UNITED STATFES OFFICE.

CHARLES P. HOLMES, OF LYNN, MASSACHUSETTS, ASSIGNOR T0 SYDNEY W. WINSLOW, 0F ORLEANS, MASSACHUSETTS.

CHAIN-STITCH SEWING-MACHINE.

To all whom it may concern:

Be it known that I, CHARLES P. HOLMES, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Chain-Stitch Sewing-Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will en able others skilled in the art to which it appertains to make and use the same.

The present invention relates to sewing machines, and more particularly to that class of sewing machines which comprise a curved hook needle and devices cooperating there with to form a chain stitch.

The primary object of the present invention is to produce a chain stitch hook needle sewing machine provided with improved thread handling devices which are simple in construction and reliable in operation, and by which each stitch can be tightened in a reliable and satisfactory manner without objectionable reeving of thread along the between substance or about the hook of the needle, and maintained in tightened condition during the formation of subsequent stitches.

With the above object in view, one feature of the invention contemplates the provision in a machine of the class referred to of a thread pusher and means for operating said pusher to engage both sides of the loop drawn out by the needle and push thereon before the work is fed to shorten the preceding loop. The last formed loop is preferably tightened about the needle when the needle again enters the work by a pull ex; erted by the take-up which thereby operates to pull the preceding loop forward and down tight against the material and set the stitch.

Another feature of the invention relates to mechanism for applying tension to the supply end of the thread whereby variations are produced in the tension applied to the supply end of the thread during different parts of the stitch forming operation.

Further features of the invention consist of certain constructions, arrangements and combinations of parts, the advantages of which will be obvious to one skilled in the art from the following description.

In the accompanying drawings illustrating the preferred form of the invention, Fig- Specification of Letters Patent.

Application filed March 22, 1912.

Patented Nov. 3, 1914. Serial No. 685,478.

are 1 is a view in front elevation of a sewing machine embodying the invention; Fig. 2 is a view in side elevation of the machine looking from the right; Fig. 3 is a view in side elevation of the machine looking from the left; Fig. 4 is a detail plan view illustrating particularly the thread pusher device and the operating mechanism therefor; Fig. 5 is a detail plan view of a portion of the mechanism for operating the thread pusher; Fig. 6 is a detail view of the slide upon which the thread pusher is mounted; and Figs. 7 to 12 inclusive illustrate diagrammatically the operations performed by the machine in sewing a seam.

The machine illustrated in the drawings is a welt shoe sewing machine of the same general type as that disclosed with substantial accuracy in the patent to French and Meyer, No. 412,704 dated October 8, 1889. The machine is provided with an oscillating curved hook needle 1, a looper 2 for laying the thread in the hook of the needle after the needle has pierced the work, a thread arm 3 to engage the thread between the looper and the work and form a loop between the needle and the work, which loop is given up to the needle during the first part of its retracting stroke, a take-up 5, a feed point (3, and a channel guide 7. The needle 1 is secured in the usual manner to the needle segment 8 pivotally mounted in a stationary portion of the machine frame and connected by a link 9 to a cam actuated lever 10. An adjustable connection is provided between the link 9 and the lever 10 to vary the amplitude of the stroke of the needle.

The thread arm 3 is secured upon one end of a shaft mounted in the stationary head of the machine, and to the other end of this shaft is secured an arm 11. The arm 11 is connected by a l nk 12 to the forward end of a cam actuated lever 13.

The looper 2 which lays the thread in the barb of the needle is provided with a shank which is received in a cylindrical socket formed in the lower end of an arm 14 which is pivoted midway its length to a block 15 secured to the forward end of a cam actuated slide 16 by which forward and rearward movements are imparted to the looper. Oscillating movements are imparted to the arm 14 to thereby impart movements to the looper at right angles to the plane of the needle, by an oscillatory rod 17 secured to an arm 18 projecting from a rock shaft 19 having a downwardly projecting arm 20 at its rear end which carries a roll engaging a cam on the cam shaft of the machine. The rod 17 is connected with the arm 14 by a rod 21 which is slidably mounted in a socket in the upper end of the arm 14 and is provided at its upper end with a hearing which receives the rod 17.

The awl or feed point 6 is secured to the awl carrier 22 pivotally mounted upon the feed slide. The mechanism for actuating the awl comprises a link 23 connecting the awl carrier with the lower end of a lever 24 which is mounted on the feed slide so as to oscillate and slide longitudinally. The lever 24 is provided at its upper end with a socket which receives a rod 25 projecting downwardly from the end of a rocking stud 26 mounted in a bore in the feed slide. The rod 25 forms a guide upon which the lever 24 slides longitudinally, and the rocking stud 26 forms a pivot upon which the lever oscillates. To oscillate the lever 24 so as to actuate the awl and at the same time permit the lever to move with the feed slide the lever is provided with a bore which receives a pin 27 projecting laterally from the lower end of a cam actuated bell crank lever 28. The channel guide is carried by the channel guide lever 29 pivotally mounted on the stud 30 and operated by suitable connections from the cam actuated lever 31.

The take-up consists of a thread truck 32 mounted on the forward end of a cam actuated lever 33. The thread, indicated at 34, after passing over the tension wheel 35 at the rear of the machine, passes over a guide truck 36 then under the truck 32 of the takeup, and then over a guide truck 37, and from thence to the looper. The arrangement of these trucks is such that the take-up operates to take up the thread during its downward movement and to deliver thread when it is moved upwardly. It is to be noted that in the illustrated embodiment of the invention the take-up mechanism does not include the usual spring actuated auxiliary take-up cooperating with the main take-up to control the thread. and that the take-up mechanism is constructed and arranged to positively control the thread dur ing the stitch forming operation. The movements imparted to the take-up during a cycle of stitch forming operations will behereinafter described.

The back rest of the machine illustrated in the drawings is indicated at 38 and the back rest slide-at 39. The back rest is yieldingly supported by a horizontal arm 40, the free end of which enters a slot in the back rest and engages a roller41 mounted therein, and the other end of which is pivotall mounted upon a vertical pivot and is yield ingly engaged with said roller by a coil spring 42.

The welt guide 43 is mounted upon a welt guide carrying arm 44 pivoted at 45 above and in front of the needle. The welt guide carrying arm 44 is connected with the Welt guide slide 46 by means of a link 47. The Welt guide is retracted at the proper times during the operation of the machine by a cam actuated lever 47 connected by means of a link 48 with a suitable clutch mechanism 49 which operates to retract the welt guide slide upon rearward movement of the lower end of the lever 47*. The welt guide is forced forwardly by means of a spring 50 coiled about a stud 51 and having an upwardly extending arm 52 which bears against a pin 53 projecting from the welt guide slide.

To lock the back rest slide 39 and the welt guide slide 46 i1:. their forward positions at the proper times during the operation of the machine, the machine is provided with a clutch mechanism comprising clutch rolls 54 and 55 arranged to engage respectively the lower and upper sides of the welt guide and back rest slides. The rolls are arranged in the same vertical plane and are fitted loosely in vertical slots in the frame of the machine. The supporting member for the rolls is in the form of a wedge 56, one inclined surface of the wedge engaging one roll and the other inclined surface engaging the other roll,. The wedge 56 is connected at its rear end to the lower arm 57 of a lever 58 pivot- .ally mounted upon a stud 59 and having a rcll at the extremity of its upper arm for engagin a cam on the cam shaft of the machine. The lever 58 is actuated by the cam to withdraw the Wedge to unlock the slides, and the wedge is moved in a direction to lock the slides by means of a coil spring 60 connected at one end to the arm 57 and at the other to a fixed point on the machine frame.

In addition to the mechanism above briefly described, the machine is provided with a thread pusher device indicated at 61 for engagement with the loop drawn out by the needle, and means to actuate the same to exert a push on the thread in a direction to shorten the preceding loop, as will be hereinafter described. The machine is also provided with a tension device constructed and arranged to a ply a comparatively heavy tension on t e supply end of the thread during certain steps in the stitch forming operation, and to apply at other times a comparatively light tension on the supply end of the thread.

The manner in which the thread pusher and the other thread handling devices cooperating therewith manipulate the thread during the formation of the seam will be clearly understood from an inspection of Figs. 7 to 12 inclusive. lln these figures 62 indicates the insole of a lasted shoe, 63 the upper, and 64 the welt. In Fig. 7 the needle is shown as passing forward through the welt, upperand the between substance of the insole, and as emerging from the channel. A loop of the thread 65 extends around the shank of the needle, and the supply side of this loop extends through a preceding loop 66 and through the work to the looper. As the needle completes its forward movement to the position indicated in Fig. 8, the take-up acts to draw the loop 65 tightly around the shank of the needle and thereby pull the loop 66 forward and down against the material, compressing the layers of' the material and binding them tightly to other. A comparatively heavy tension is app led to the supply end of the thread durin this action of the take-up until an instant efore the take-up completes its loop drawing stroke, when the heavy tension is released and a comparatively light tension is applied to the supply end ofthe thread. The loop 65 is drawn tight about the shank of the needle, and the loop 66 is drawn forward while the heavy tension is applied to the thread, so that the stitch is tightened in a satisfactory manner. The slight movement of the take-up after the heavy tension is released enables the take-up to draw from the supply a portion of the thread necessar for the succeeding stitch. WVhile the nee le is still in the position illustrated in Fig. 8, the thread arm acts to form a loop between the needle and the work and the looper lays the thread in the hook of the needle as indicated in Fig. 9. The supply end of the thread is still under light tension and the thread arm operates to pull thread through the light tension from the supply. In addition to assisting in supplying thread for the succeeding stitch, this operation of the thread arm automatically takes care of variations in the amount of thread pulled from the supply by the take-up. The looper also pulls thread from the supply during its movement about the needle and the take-up moves slightly to give up a small quantity of thread during the operation of the looper. The needle now retracts and draws a loop of thread throu h the material and through the loop 65, as il ustrated in Fl .10. The thread arm gives up its loop to t e needle during the retracting stroke of the needle, and the take-up o crates to deliver thread to the supply si e of the needle loop so that the thread does not reeve through the hook of the needle and no injurious strain is brought upon the thread or the work, since the needle pulls its loop against very little resistance. The supply end of the thread is under light tension during the greater part of the loop pulling stroke of the needle, but 'ust before the needle reaches the end of its loop drawing stroke the heavy tension is applied to the thread so that the final tug of the needle is against heavy tension. This final tug of the needle against the heavy tension is merely sufiicient'to take the resiliency out of the thread and draw it taut. The needle at the completion of its retracting movement reaches the position indicated in Fig. 10, in which position it will be noted that the loop 65 extends around the loop drawn out by the needle, and is of'a length sufficient to reach from the preceding needle hole to the last needle hole.

To cause a tight seam to be formed when the loop 65 is drawn forward, the slack thread should be removed from the loop 65 and the loop drawn back of the last needle hole. To secure this result a thread pusher 61-is moved forward as illustrated in Fig. 10 into engagement with both sides of the loop drawn out by the needle, and is then further advanced, as illustrated in Fig. 11, toward the work and in the general direction of the seam, or in the direction of feed. This advancing movement of the pusher after it has engaged the thread pushes both sides of the needle loop in the direction of the previously formed seam and the tension exerted by the pusher upon the thread leading to the precedin loop shortens said loop so that the end of t e loop is drawn back of the last needle hole. This loop shortening action is facilitated by the action of the pusher in deflecting both sides of the loop drawn out by the needle in a direction away from the forward extremity of the preceding loop, so that the needle loop does not exert any strain on the forward end of the prece ing loop tending to draw the preceding loop forward. During the loop shortening action of the pusher the take-up is operated to deliver' thread on the supply side of the loop drawn out by the needle just sufficient to permit the thread pusher to deflect the supply side of the needle loop and still keep the supply end of the thread taut. This action of the take-up to deliver just the amount of thread required by the thread pusher prevents the thread from rceving about the hook of the needle during the loop shortening operation, and also prevents any objectionable strain on the needle. By the action of the thread pusher the loop 65 is shortened accurately and to the desired extent so that when it is subsequently pulled forward the stitch of which this loop forms a part tightly compresses and binds the layers of material together. After the loop 65 has been shortened as indicated in Fig. 11, the'thread pusher is retracted to release both sides of the needle loop, and the work is fed the length of a stitch. This movement of the work brings the parts into the relative positions illustrated in Fig. 12. with the needle still at the limit of its back stroke, and with the loop of needle thread extending from the book of the needle to the preceding loop 65. The needle now passes forward and pierces the work, as indicated in Figs. 7 and 8, and during this movement of the needle the take-up acts to pull thread from the needle loop and finally pulls the needle loop tightly around the shank of the needle and the preceding loop forward and down against the material.

It is preferred to employ a take-up mechanism in which the usual spring actuated auxiliary take-up is eliminated and which is constructed and arranged to positively control the thread. The actuating mechanism for the take-up is also preferably constructed to start the taking up movement of the take-up simultaneously with the forward or work piercing movement of the needle.

By actuating the thread handling devices in the manner above described, the thread is manipulated so as to form a satisfactory seam about all of the difierent portions of the margin of the shoe.

The primary function of the thread pusher is to push against the needle loop and thereby shorten the preceding loop. It will be seen, however, from an inspection of Figs. 11 and 12, that in addition to shortening the preceding loop the pusher pushes against the needle loop after the needle is retracted and before the work is fed, and thereby provides a sufiicient amount of slack in the needle loop to enable the work to be fed without causing the needle loop to exert an objectionable lateral strain on the needle. The work can therefore be fed easily without bringing any injurious strain upon the needle, the thread or the work, and without interfering with the manipulation of the work by the operator.

The pusher device illustrated in the drawings consists of a cylindrical rod 67 bifurcated at its forward extremity to form a thread receiving notch. This rod is adjustably clamped in a socket 68 formed on an arm 69 extending upwardly and forwardly from a slide 70 arranged to reciprocate in a guide 71 carried by and preferably formed integral with the frame of the machine. The slide is held in the guide 71 by a retaining plate 72. The guide extends forwardly and downwardly in an angular direction toward the point of operation of the stitch forming mechanism, as illustrated in Figs. 1, 2 and 4. The slide 70 is actuated to give the desired movements to the thread pusher by mechanism comprising an oscillatory lever 7 3 having an arm 7 3 provided with a bearing 74 at its forward extremityin which a rod 75 is arranged to slide, said rod having a bearing 76 at its forward end adapted to receive apin 7 7 projecting downwardly from the slide 70. Reciprocating movements 'are imparted to the slide 7 O by the oscillatory movements of the lever 73,

and during the movements of said lever the rod 7 5 slides in the bearing 74 and the rod 7 7 slides in the bearing 7 6. The lever 73 is pivoted upon the stud 78 carried by an arm 79 projecting rearwardly from the frame, and has a second arm 80 connected with the arm 7 3 by a web 81, and provided with a cam roll 82 at its forward extremity which engages a cam carried by the cam shaft of the machine. The rod 67 is adjustably mounted in the socket 68 so that the thread pusher may be adjusted with relation to the needle, and the movements of the pusher after it engages the thread varied, and therefore the extent of the loop short ening action of the pusher may be varied.

The machine illustrated in the drawings is provided with a tension device and means to actuate the tension device to exert a comparatively heavy tension from the last portion of the loop drawing stroke of the needle until just before the take-up completes its taking up stroke of the take-up, and to exert a comparatively light tension on the thread during the remainder of a cycle of stitch forming operations. The machine is also provided with a tension releasing mechanism actuated by a backward rotation of the cam shaft of the machine. The tension wheel 35 over which the thread passes on its way to the truck 36 is mounted on a shaft 83 journaled in the machine frame, and a brake wheel 84 is fast on one end of the shaft 83. A brake shoe 85 for engagement with the brake wheel 84 is mounted on one arm of a bell crank lever 86 pivoted on a stud 87, and the lever 86 is actuated to hold the brake shoe yieldingly in engagement with the brake wheel by a coil spring 88 surrounding a rod 89 pivotallyconnected with the horizontal arm of the bell crank lever and operating in a perforated lug 90 on the frame, said sprin engaging the lug 90 and a nut 91 threaded on the rod. A. secondbrake shoe 93 oppositely disposed to the brake shoe 85 is arranged to engage the brake wheel 84, and to this end is mounted upon a lever 94 pivotally mounted upon a stud 95 formed integral with said lever. A rod 96 is pivotally connected with the extremity of the lever 94, and operates in a perforation in the portion 97 of the frame. The brake shoe 93 is yieldingly held in engagement with the brake wheel 84 by a coiled spring 98 which surrounds the rod 96 and engages the portion 97 of the frame, and an adjustable nut 99 threaded on the rod 96. The brake shoe 85 is constantly held in engagement with the brake wheel by the spring 88 and the variations in tension are produced by moving the brake shoe 93 into and out of contact with the brake wheel. In order to release the brake shoe 93 from engagement with the brake wheel 84 at certain points in a cycle of operation of the machine, an arm 100 is 1,11e,aua

rigidly mounted upon the stud 95 which supports the lever 94, and is arranged to be engaged by an arm 101 of a lever 102 pivoted upon the stud 59 and provided with an arm 104 which carries a cam roll for engagement with a peripheral cam on the cam shaft of the machine. The cam roll is held in engagement with the cam by a coiled spring 104. In the present embodiment of the invention the cam which operates the lever 102 is constructed to actuate said lever to cause the release of the brake shoe 93 from the brake wheel 84 an instant before the take-up reaches the end of its loop-drawing or taking-up stroke, and to maintain the brake shoe 93 out of engagement with the brake wheel 84 until just before the needle reaches the end of its loop-drawing stroke. At this time the lever 102 is actuated by the spring 104 to permit the brake shoe 93 to be yieldingly engaged with the brake wheel by the spring 98, thereby causing a comparatively heavy tension to be applied to the thread.

In order to completely release the tension wheel 35 from tension when the cam shaft is reversed to disengage the thread from t1" a needle at the end of the sewing operation, a bell crank lever 106 is pivotally mounted at 107 on the machine frame, and is provided with an upwardly extending arm 108 which carries a pin or rod 109 pivotally connected with said arm and engaging a recess in an upwardly extending arm 110 of the lever 94. The forwardly extending arm 111 of the lever 106 is provided with a recess 112 which is arranged to be engaged by the extremity of a rod 113 pivotally connected with the rearwardly extending arm of the bell crank lever 114 pivotally mounted on the shaft 59. An arm 115 is pivotally connected with the other arm of the bell crank lever 114 and is provided with two curved surfaces 116 and 117 arranged at different distances from the pivot of the arm for engagement with a collar 118 attached to the cam shaft of the machine. The collar 118 is provided with a notch 119 which is adapted to engage a projection 120 on the arm 115 between the surfaces 116 and 117. When the machine is operating to sew a seam the arm 115 is in the position illustrated in Fig. 3. At the end of the sewing operation the direction of rotation of the cam shaft is reversed, and the arm 115 is swung upwardly by the engagement of the notch 119 with the projection 120, bringing the surface 117 into engagement with the collar 118. The arm 115 is moved longitudinally at the same time that it is swung by reason of the fact that the surfaces 116 and 117 are at different distances from the pivotal point of the arm, and this longitudinal movement of the arm moves the bellcrank 114 to the left (Fig. 3) about its axis, and depresses the rod 113. The rod 113 is provided with a shoulder 121,

located above the horizontal arm of the lever 86. When the rod is depressed the shoulder 121 engages the lever 86 and moves the brake shoe 85 out of engagement with the brake wheel 84, and the lower end of the rod 113 engages the forwardly extending arm of the lever 106 and actuates said lever and thereby the lever 94 in a direction to release the brake shoe 93 from the brake wheel. The reversal of rotation of the cam shaft therefore throws both brake shoes out of operation and releases the tension on the thread, so that the work can readily be removed from the machine.

The welt guide slide is connected with the tension releasing mechanism so that the welt guide is retracted when the shaft is reversed; To this end a rod 122 is mounted in the rear end of the 'welt guide slide, and a nut 123 mounted on the rod is arranged to be engaged by the vertical arm of the lever 106 when said lever is actuated by the reversal of the shaft. The lever 106 is held in normal position so as not to interfere with the movements of the welt guide slide by a coiled spring 124 interposed between the vertical arm of said lever and a stationary part of the frame.

Although the invention has been illus trated as embodied in a chain stitch sewing machine of the type described in the French and Meyer Patent No. 412,704, it is to be understood that certain features of the invention are not limited to any particular machine or type of machine for sewing a chain stitch seam, and, that except as defined in the claims the several features of the invention are not limited to any particular construction or arrangement of parts.

Having explained the nature and object of the invention, and having described a machine embodying the same in its preferred form, what is claimed is 1. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a pusher, and means for actuating said pusher to engage both sides of the loop drawn out by the needle and push thereon in the general direction of the previously formed seam before the work is fed to shorten the preceding loop back of the last needle hole and provide slack in the needle loop, and means for feeding the work while said slack remains in the needle loop, substantially as described.

2. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a thread pusher, and means for actuating said pusher to engage both sides of the loop drawn out by the needle and push thereon in the general direction of the previously formed seam to shorten the preceding loop back of the last needle hole, substantially as described.

3. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through av previously formed loop, means for feeding the work, a thread pusher, and means for actuating said pusher to engage both sides of the loop drawn out by the needle and push thereon in the general direction of the previously formed seam before the work is fed to shorten the preceding loop back of the last needle hole, substantially as described.

4. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a thread pusher acting on the loop in the general direction of the previously formed seam, means for actuating the said pusher to engage both sides of the loop drawn out by the needle and push thereon to shorten the preceding loop, and means for relieving the supply side of the needle loop of strain while the preceding loop is being shortened, substantially as described.

5. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a pusher acting on the loop drawn out by the needle in the general direction of the previously formed seam, means for actuating the pusher to engage both sides of the loop drawn out by the needle and push thereon to shorten the preceding loop back of the last needle hole, a take-up, and means to operate the take-up to exert a stitch setting strain on the seam while the needle is in the work and to deliver thread on the supply side of the needle loop during the loop shortening operation of said pusher, substantially as described.

6. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a pusher acting on the loop drawn out by the needle in the general direction of the previously formed seam, means for actuating the pusher to engage both sides of the loop drawn out by the needle and push thereon to shorten the preceding loop back of the last needle hole, a take-up, and means to operate the take-up to exert a stitch setting strain on the seam whilevthe needle is in the work and to deliver thread and keep the thread taut during the loop shortening operation of said pusher, substantially as described.

7. A chain stitch sewing machine, having, in combination, stitch forming devices in cluding a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, means acting on the loop drawn out by the needle in the general direction of'the previously formed seam to shorten the preceding loop, a take-up acting to deliver thread during the loop shortening operation and to extend a stitch setting strain on the seam While the needle is in the work, a tension device, and means to actuate the tension device to exert a heavy tension on the supply end of the thread from the conclusion of the loop drawing stroke of the needle until just before the end of the stitch tightening operation of the take-up and to exert a light tension on the supply end of the thread at other times during a cycle of stitch forming operations, substantially as described.

8. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, a thread pusher to engage the loop drawn out by the needle and exert a push thereon to shorten the preceding loop, an angularly arranged slide on which the pusher is mounted, a cam actuated oscillatory lever and connecting mechanism for reciprocating the slide from the lever comprising a pin projecting downwardly from the slide, and a rod arranged to slide in a bore in said lever and having a bearing to receive said pin, substantially as described.

9. A chain stitch sewing machine, having, in combination, stitch forming devices in cluding a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, means acting on the loop drawn out by the needle in the general direction of the previously formed seam to shorten the preceding loop, a positively actuated take-up acting to exert a stitch setting strain on the seam while the needle is in the work and constituting the sole means for taking up the loop of thread drawn out by the needle, and means for actuating the take up to control the thread, sub stantially as described.

10. A chain stitch sewing machine, having, in combination, stitch forming devices including a hook needle operating to draw a loop of thread through the materials and through a previously formed loop, means acting on the loop drawn out by the needle in the general direction of the previously formed seam to shorten the preceding loop, a positively actuated take-up acting to exert a stitch setting strain on the seam while the stitch setting strain on the seam while the needle is in the work and constituting the sole means for taking up the loop of thread drawn out by the needle, and means for actuating the take-up to begin its take-up action simultaneously with the forward movement of the needle, substantially as described.

CHABLES P. HOLMES.

Witnesses FRED O. FISH,

GEORGE E. STEBBINS.

Copies of this patent may he obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. 0." 

